1. Field
This invention relates generally to hip surgeries and, more particularly, relates to surgical methods, tools and implants for treating femoral acetabular impingement.
2. Related Art
Femoroacetabular impingement or FAI is a condition of the hip joint where the femoral head and acetabulum rub abnormally creating damage to the hip joint. The damage can occur to the articular cartilage of the head or acetabulum or to the labral cartilage on and around the acetabular rim.
Specifically, FAI may take one of two forms: cam or pincer. The difference between the two forms is determined by the abnormality of the hip joint that is the cause of the damage. The cam form of FAI occurs when the femoral head and neck relationship is aspherical, or not perfectly round. This loss of roundness contributes to abnormal contact between the head and socket. The pincer form occurs when the acetabulum has too much coverage of the femoral head. This over-coverage typically exists along the front-top rim of the acetabulum and results in the labral cartilage being “pinched” between the rim of the socket and the anterior femoral head-neck junction. In most cases, the cam and pincer forms exist together (thus creating a compound form of FAI).
Treatment of FAI may be accomplished by surgical intervention. Arthroscopically, the hip may be scoped to assess the hip joint and treat damage that is found through two to four 1 cm incisions. Often, all of the components of FAI such as the labral tear, damaged cartilage, and friction between the ball and socket can be treated through the arthroscope. Repair may include debridement, microfracture techniques, labral repair, and bony decompression. Care must be taken to avoid damage to the hip's blood supply during the osteoplasty procedure.
An open surgical technique requires hip dislocation through an incision (approximately 6 to 10 inches). An upper thigh bone osteotomy allows for dislocation of the femoral head from the socket exposing all parts of the joint. This exposure allows treatment of labral tears and abnormal contact between the ball and socket while protecting the blood supply to the hip. In both of these types of treatment, bone removal and repair are employed to address FAI.